Internally insulation lined vessel



n 3, 1 E. R. THOMPSON INTERNALLY INSULATION LINED VESSELS Filed Oct lA/VE/VTOR w v1rllllllfI/II!IIIIIIIIIIIIIIIl/l 7 ATTOIM'EY Patented June 3, 1952 Elliott-.8. Thompson, Merchantville, N. L, as-

signer tolhe M. W..Kel e1gv Company, :New York, .N.,SZ-, a cnrnorationof Delaware Application-October 11, 1945, Serial No.621},'760

12 Q aims.

This invention relatesv to internally insulated vessels designed to handle. materials: .high temperatures.

It has become necessary in many arts' to provide vessels capable of handling materials; at temperatures well above :the :range..-in which carbon steel is a satisiactorywmaterialnieconstrnction. Vessels for this .class .ofseryicezhaue been made of high creep strength alloys. v:ef "various analyses. such alloy vessels ha enbe n iound satisfactory in many installations but the cost of the alloys, the difficulties. attendant. their fabrication, the special heat treatmentsreduired and the maintenance and repair problems render such alloy vessels costly and-troublesome.

It has been proposed to. eliminate the necessity f r hi h creep strength alloys by employ ng a heat insulating lining against the-inner walls of the vessel to .reduce their temperatureto the ran e in which carbon 'stee1..-is.;tully satisfactory. The insulating linings of thischaracte-r that have gone into use usually include adepth of insulation which is separated by a comparatively thin metal liner element from-the material handled. Since the metal linerelement isnot designed to withstand the operating pressures,. nrov-ision is made for pressure equalization throughout. the cross-section of the vessel.

Internal insulation 1ini-ngs,-;-in order to properly serve their purpose, mustrbeqso constructed and arranged that their insulating; value remains, unimpaired in service. The chief causef loss: of insulating value in service lstheflow ofmaterial through the space occupied. by the insulation component of the lining. Aniarppreeiable how of the material through the spaceoccupied :by the insulation component will raise the temperature of the vessel walls above the rangetor-which they are designed. If the flow is. pronouncedhot-spots may develop which sometimesapproachtheztemperature of the material handled. also. vflow of material through the space occupied by them,- sulation component may at times. removethe insulation itself. These causes may Produce .a

d r us c nd t on that -ultimately-..-results in failure of thevessel.

To prevent flow of the material handled through the space occupied by the insulation component it has been proposed to divide such space into a number of chambers separated from one another by elements imperviousrto the fl JW of the material handled. The impervious separating elements are usually united to the vessel walls and to the metal ,liner elements .and.5 ;P'

port the metal. liner elements imposition.

' these-proposalsare. a step in the right direction they-are of little value unless the metal liner elementin any-position of use..or underany condition of operation, can expand and contract without substantial restraint; otherwise, it will warp and distort to permit undesired flow of the material handled through the space occupied by :the insulation component. Also, it is necessary thatx-the imperviousseparating elements be of such form and construction that they not only .do not. offer substantial restraint to the expansion and .contraction movements of the metal liner-elements but theythemselves expand and contract with .a minimum of restraint to the end that disruptive stresses are not. set up within them that would cause the joints between the impervious separating elements and the vessel walls or the joints between the impervious separating element and the metal liner elements to fail and thus, provide passage for substantial flow of the material handled through the space occupied by the insulation component of the liner.

Hot-spots may also appear because of voids in the -iI-isulation formed by packing and movement of :theinsulation through the expansion and contraction of the metal liner elements and their supporting: elements. To eliminate, or atleast reduce to a minimum. hot-spots that appear throu h: this cause, the arrangement and construction of the metal liner elements and their supporting elements should ,be such that their expansion and contraction movements have a minimum tendency to move or packthe insulation.

Flow in the space occupied by the insulation may also take place due to failure oivthemetal liner: element by erosion. .In strai ht runs erosion is usually note Serious problem'bu-t in runs wherein the direction of now of the material handled is changed,..erosion can be serious, especially if the ,material handled includes solid particles. It has become-accepted practice to protect sections of the insulation lining subject to erosive wear by increasing the thickness of -the metal liner element. This expedient is only a partial solution, Erosion does not take place evenly vso that even with a-thicker' metal'liner element a great-deal ofchecking and inspection ,is necessary; also, tor the same reason, there is no warning of failure. Welds, especially cir- .cum-ferential welds that Project into the flow stream, are especially subject to wear ,by :erosion,

and increasing the thickness .of the metalliner elements-in nowise reduces their susceptibility 3 to wear. Furthermore, when failure of the metal liner element occurs, or the metal liner element is worn to the danger point, repair generally involves rebuilding a large section of the insulation lining.

It is a primary object of this invention to provide a novel internal insulation lining for vessels which includes an insulation component separated from the material handled by a metal liner element supported in any angular disposition of the vessel by a continuous, impervious member united to the vessel walls and to the metal liner element to provide an impervious barrier to the flow of the material handled through the space occupied by the insulation component and to permit substantially unrestrained radial and longitudinal expansion and contraction of the metal liner element; the impervious member being such that it expands and contracts with a minimum of restraint and without setting up within it substantial disruptive stresses tending to tear the joints that unite it to the metal liner element and to the vessel walls; the arrangement of the impervious member and metal liner element being such that substantial packing of the insulation component or creation of voids therein does not result by reason of the expansion and contraction of the impervious member and the metal liner element. It is a further important object of the invention to provide in the novel internal insulation lining mentioned, an impervious support member made up majorly of a normally cylindrical support member arranged to expand and contract with a minimum of restraint and so united to the vessel walls and to the liner element that the forces set up in it due to expansion and contraction do not have their effect directly at the joints uniting the impervious support member to the vessel walls and the metal liner element. It is also a major object of the invention to provide in the novel internal insulation lining mentioned a simple erosion protection arrangement which does not materially restrain the radial or longitudinal movement of the metal liner element while it effectively protects the metal liner element and the welded joints therein, the arrangement being such that checking and inspection are reduced to a minimum and a definite warning is given before the metal liner element is attacked,

the arrangement, furthermore, being such that it may be readily and cheaply replaced in whole or in part without rebuilding or disturbing the insulation lining.

The further objects, features, and advantages of the invention will be readily apparent from the following description of a present preferred embodiment of the invention taken with the accompanying drawings, in which:

Fig. 1 is a sectional view illustrating the invention as applied to a cylindrical vessel;

Fig. 2 is a view similar to Fig. 1 of a vessel having a bend therein; and

Fig. 3 is an enlarged sectional view of a detail of the invention.

The novel internal insulation lining of the invention is of general application and may be applied to vessels, pipes, conduits, and the like that are used for handling, storing, processing, or flowing solids, gases, vapors or mixtures thereof. By processing it is intended to include operations in which combustion takes place directly in vessels, pipes, conduits, and the like.

Hereinafter, the term vessel will be used to,

indicate and to include all forms of apparatus to which the novel internal insulation lining may be applied. The novel internal insulation lining may be applied to vessels of any size or shape and is usually formed to conform to the internal shape of the vessel. Since it is more usual to line vessels having a generally circular transverse cross-section, the invention will be described and claimed in connection with such vessels without intention, however, of limiting it to such vessels. While the vessels to which the novel internal insulation lining of the invention is applied are intended to handle materials at elevated temperatures and usually also at elevated pressures, the invention is not limited to vessels handling high temperature materials as, obviously, the novel lining is useful even at very low temperatures. Thus, the novel internal insulation lining may effectively be used to line vessels handling gases and other materials at temperatures in the range in which carbon steel is not satisfactory because of its low shock resistance, so that by reason of the novel lining the temperature of the vessel walls can be kept above said range. Vessel l0, shown in Fig. 1 as a straight length of pipe, includes a wall II formed with flanges 12 at its ends. Wall H is preferably, though not necessarily, made of carbon steel. When made of carbon steel it is usually designed for temperatures not substantially in excess of 650 F. Against wall II is disposed insulation material l3. The depth of insulation material 13 employed is such as is necessary to provide the required temperature difference between the material handled and the wall ll of vessel It. The material handled, may, for example, be high pressure steam at about 1800 F. In such case, the depth of insulation l3 must be sufficient to provide a heat barrier capable of keeping the temperature of wall H at or below the chosen temperature for which walls I I are designed.

Insulation material l3 may be of any preferred kind and character suited to the service. At present, it is preferred to use insulation material of such kind and in such form that it may be easily applied to the inner surface of the walls of the vessel and shaped to conform to the contour of said surface. An insulation made up of amosite asbestos, diatomaceous earth and a suitable binder has been found satisfactory for the service mentioned above.

Insulation material I3 is separated from the material handled by metal liner element M which is made up of a plurality of sections [6. The sections of metal liner clement l4 may be made of any metal suitable for the service. If the material handled is non-corrosive, and carbon steel is sufficiently strong at the operating temperature to hold its shape, carbon steel may be used since metal liner element 14 is not designed to withstand the operating pressure. If the material handled is corrosive or carbon steel is not strong enough to keep its shape at the operating temperature, corrosion resisting alloys having superior high temperature creep strength such as chrome steel or chrome-nickel steel, and the like, may be used. 7

Sections I6 are each formedof two sub-sections, usually equal in length, united to each other and to T-ring I! by circumferential weld I8. Each of the sub-sections is formedfoutof one or more sheets of the proper lengthof metal of the chosen analysis and gage united at theirabutting edges by longitudinal welds to form an openended cylinder. The subsection forming the downstream end of section [6 has united to its inside face and near the end thereof a. narrow buffer ring l9 and a lap ring by means of weld deposits 2! and 22. Buffer ring '13 serves to prevent failure or dislodgement oflap ring 2 0 by protecting weld 21 from erosive wear which is generally excessive in circumferential welds that project into the flow stream of the material handled. To the outside face of the same subsection end is united a smaller lap ring 23 by a circumferential weld. The annular groove provided by lap rings 20 and 23 is adapted to lit the upstream end of the nextsection Hi, the ends of the sections being properly spaced to provide for their longitudinal expansion and contraction movements. The expansion joint thus formed also provides a passageway for pressure'equalization in the space occupied .by'insulation 13. Lap rings 28 and 23, aside from performing their joint forming functions, serve :to stiffen the .ends of the sections against distortion and strengthen them against collapse; these lap rings also serve to maintain the section ends in alignment during their expansion and contraction movements, and, furthermore, prevent direct impingement of the material handled on insulation material 13 as well as aspiration thereof during .rapid pressure equalization.

The downstream end of the downstream section It terminates adjacent the end of pipe I!) andhas united thereto .a 'lapring 20 and a buffer ring 19. A portion of this :lapring 20 extends .into the next vessel Ill and telescopes into the end of metal liner I l thereof. Weld 2|, uniting lap ring 29 to the metal liner element [4, is protected against erosion by a buffer ring l9, united to the metal liner element l4 by circumferential weld 22. This lap ring 20 serves .to stiffen the ends of metal liner elements l4 and I4" and strengthens them against collapse while it serves to maintain them in alignment during expansion and contraction. This lap ring 20, furthermore, protects the space between metal liner elements l4 and 14 provided for pressure equalization against direct impingement by the material handled and prevents aspiration of insulation onsuddenpressure equalization. Near the :ends of vessels H1 and i 0. are welded rings v2'6 and 26, which serve to hold rope insulation 21, or packing insulation :inother form, in position when the joint between vessels It and i0 is closedby taking'up on the :bolts, not shown, that pass through theholes in fiangerings 28 and 28'.

Each of the T-rings l-l, as'bestshowhin FigS, is united to an elongated normally cylindrical member 36. Cylindrical member 30 is united to a ring 3i which, in'turn, is united to. wall ll of vessel iii. The transverse web of T-ring 'l'l is made stiff enough to resist deformation by cylindrical member 39 during expansion and contraction movements. The end of the web of T-ring H is positioned sufficiently away from the end of cylindrical member 30 topermit it to be united to cylindrical member 30 by circumferential welds 32 and 33. Ring 3i is united to wall 10 by a-circumierential weld 34 deposited on the side of ring 3! away from T-ring ll. Asubstantial-portion of cylindrical member 30 bears on ring '31. The end of the bearing portion of cylindrical member 38 is united to ring 31 by a circumferen tial weld deposited on thesamesideo'f-rin 31 as weld 3t. Cylindrical'member 30is chosen-thin enough to readily flex under, the influence of stresses set up'thereindue to ring 11 andring 3|.

Cylindrical members Stand T rin'gs I 1 provide impervious barriers 'tothe flow of the material 8 handled through the space occupied-by insulation -13 and serve to separatesaid space intoa plurality of bulk-headed compartments from one to another of which the material handled cannot now. Each of these bulk-headed compartmentsghowever, is provided at or near its middleregion with a ring l'ike passage of controlledsize, thepassage provided by the expansion joint, through which communication between the central space enclosed by metal liner element 14 and the space occupied by insulation I3 is had for pressure equalization.

The insulation l-ining may be applied during fabrication of the vessel-0r immediately thereafter or itmay be-applied after the vessel is positioned for user This will generally depend on thesize and shape of the vessel. In anyevent, as much of theinsulating lining, or its components, will be fabricated outside of the vessel as is possible.

Assuming that vessel It is a large size pipe that affords ready man access, the insulation lining may be applied in a convenient mannerby initially positioning all of rings 3| and uniting them to wall-l I by means of welds 34. This permits rings 3i to be accurately positioned as the internal space of vessel It! is at this time unencumbered with other parts. Cylindrical members 30, previously having had T-rings I1 united thereto, are-next positioned and united to rings 3 l. Flat rings 26'are then positioned and united to the vessel wall H. Insulation material [3 is nextapplied-tovessel wall I l. Insulation [3 is not positioned in the space between cylindrical member 39 and vessel wall I] The metal sheets, in the flat form or in a partly or fully shaped condition, necessary to form the upstream and downstream sub-sections of sections l6, are then moved into the vessel and assembled. In this assembly care must be taken to space the ends of the sections to provide sufficient room for expansion. After the sub-sections are complete the proper pairs of sub-sections are united to each other and to their T-rings H by depositing welds Hi. It is to be noted that the sheets used to form thedownstream sub-sections should havelap .ring 23, or the component parts thereof, united thereto before such sheets are moved into the vessel Hi. It is also preferred to unite buffer rings i9, or the component parts thereof, to the sheets used to form the downstream sub-sections before such sheets are moved into vessel Ii). Lap .rings '20 and 24 are then moved into position and united to the section ends and to bufier rings 19 :by depositing circumferential welds 2i.

Rope insulation 21 is positioned prior to closing the-joint between vessels I0 and It by-taking up on the bolts, not shown, that pass through the bolt holes in flange rings .28 and 28'.

In service the heat of thematerial handled will cause radial and longitudinal expansion of the metal liner element 14. Considering first radial expansion; as liner I4 increases in temperature it will expand in the direction of the walls ll. Since it can be presumed that the whole of the metal liner of any of the sections I6 will attain a substantially'uniform temperature, the. temperature rise will resultin a uniform increase in diameter of the whole of the section I 6. Since T-ring l1 is-welded directly to its liner section It, ring I! will attain atemperature approximating that of the liner section. Thus, T-ring II will increase iii-diametersubstantially to-the same extentas-its-liner section .atfiandwill offer no I appreciable restraint .to the expansion thereof. Heat will be transmitted from T-ring I! through cylindrical member 30 to ring 3| and finally to the wall of vessel I. A substantial temperature drop will take place in the length of cylindrical member 30. Thus, the expansion of cylindrical member 30 will cause it to assume a shape approximating that of a truncated cone, see dotted line position in Fig. 3. The greatest diameter will be found adjacent T-ring l1 and the smallest diameter adjacent ring 3|.

As stated, the web of T-ring I1 is made strong and stiff enough to resist deformation by forces set up in cylindrical member 30 while cylindrical member 30 is made flexible enough to deflect or bend under such forces, hence expansion, or restraint in expansion, of cylindrical member 30 will have no appreciable deforming or restraining effect on T-ring I! nor on the metal of the section l5 of liner l4. Since a temperature drop occurs in the length of cylindrical member 30. T-ring I! will exert an effect on cylindrical member 30, that is, it will tend to enlarge the diameter of the end region of cylindrical member 30 united to it beyond that to which such region tends to expand to by reason of the temperature rise. This results in deflection line B, shown as point B in Fig. 3, about which cylindrical member 30 will bend or tend to bend towards wall The opposite end of cylindrical member 30 attains a higher temperature than ring 3|. Cylindrical member 30 will thus tend to expand beyond the diameter permitted by ring 3| and wall I and bends, or tends to bend, about line A, shown in Fig. 3 as point A. The forces causing or tending to cause the deflections about lines A and B are the only substantial forces set up in cylindrical member 30 by reason of the temperature rise. It is to be noted that the forces mentioned do not act directly on the welds that unite cylindrical member 30 to T-ring l1 and to ring 3| but rather are effective at most to flex the walls of cylindrical member 30. The forces mentioned cannot, therefore, tear the joints if the welds forming the joints are properly designed to carry the weight loads.

The rise in temperature also results in cylindrical member 30 increasing its length but, since cylindrical member 30 does not attain a very high temperature and is comparatively short, the effective increase in length if any, is so small that it imparts no consequential movement to T-ring l1 and the section l6 of liner l4 carried by it. Since the metal of the section I6 is united to its T-ring I! only by the narrow weld Hi, there is no restraint tothe longitudinal expansion of the section l6 as the metal of the section l6 can freely expand from weld l8 to its ends. Since weld I8 is located in the middle, or near the middle of the section IS the movement of any portion of the liner metal is a minimum. Thus, by this construction there is a minimum movement of the parts tending to move or pack insulation i3 and to form voids therein.

Referring now to Fig. 2, vessel 50 is of the same character as vessel I0, above described, and is made up of a straight run and a curved run 52, for convenience only two sections 53 and 54 of the curved run, are shown. Vessel 50 includes the novel insulation lining already described and, in addition, the novel erosion protection arrangement of the invention. The elements of the novel insulation lining have been identified by the same numerals used in Figs. 1 and 3. The construction of .theinsulation lining is the same but the elements of the lining vary in form where necessary to conform to the shape of the vessel 50 they are associated with.

Metal liner element M, of vessel 50 of Fig. 2, is made up of sections I6, 55 and 56. Section I6 is found in straight run 5| and is generally the same as section l6 of Fig. 1. Sections 55 are found at the joint between straight run 5| and curved run 52 and at the joints between the sections 53 and 54 of curved run 52. Section 56 is found between the ends of sections 55 in section 54. Whether two sections 55 are used, as in section 53, or a section 56 is interposed between section 55, as in section 54, will dependon the service. These arrangements are in the nature of alternates.

Sections I6, 55, and 56 have their entire surfaces covered by wear members 58. Wear members 58 are shaped to conform to the shape of the portion of metal liner element l4 they cover. The wear members are arranged in shingle fashion so that they shield all portions of metal liner element l4, including all welds therein, as well as all circumferential welds in wear members 58 themselves, from the stream of the material handled. A wear member 58 is united to each of sections 55 and 56 at the ends thereof to which lap ring 23 is united to form an expansion joint. The wear members 58 have all of the functions of lap rings 20 of the construction of Fig. 1. Wear members 58 are also united to sections 55 and 56 in the region of welds I8. These wear members 58 extend somewhat upstream from welds l8 so as to cover them.

It is to be noted that wear members 58 are so supported that they can freely expand and contract without appreciably restraining or being restrained by the sections of metal liner element M to which they are united and without putting loads on rings tending to warp or distort metal liner element I4.

I claim:

1. A vessel, an insulation lining positioned adjacent the inner face of the walls of said vessel, said lining including a depth of insulation and a metal liner element between said insulation and the material handled in the central space of said vessel, and impervious means supporting said metal liner element while permitting substantially unrestrained radial and longitudinal expansion and contraction thereof, said impervious means including a member encircling said metal liner element and united thereto and extending into the space between said metal liner element and the walls of said vessel in a plane transverse to the longitudinal axis of said metal liner element, said encircling member expanding and contracting radially with said metal liner element without substantial restraint to said liner element, and a second member encircling the extending end of said first encircling member and having one end united thereto, said second member being in the shape of a surface of revolution and having its other end united to the walls of said vessel.

2. A vessel, an insulation lining positioned adjacent the inner face of the wall of said vessel, said lining including a depth of insulation and a metal liner element between said insulation and the material handled in the central space of the vessel, and impervious means united to said metal liner element and to the vessel walls supportin said metal liner element while permitting substantially unrestrained radial and longitudinal expansion and contraction thereof, said impervious means including a ring of T cross-section encircling said metal liner element and united thereto, the webof said ring extending into the space between said,- metal liner: element and the walls of said: vessel in, a plane transverse to the longitudinal axisv of said metal liner element, a substantially cylindricalmember' encircling said web with one end adjacent said web and united thereto, and means uniting the other end of said cylindrical member to the vessel walls, said web being of sufficient strength to resist restraint by said cylindrical member during expansion and contraction. a 7

3. A'vessel, an insulation lining positioned adjacent. the inner face of the wall-s of said vessel, said, lining including a depth of insulation, a metalv liner element. between said insulation and the central space of said vessel, and impervious means united to said metal liner element and to the walls of said vessel supporting said metal liner element while permitting substantially unrestrained-[radial and longitudinal expansion thereof, said impervious mean including an elongated member in the shape of a straight-sided surface of revolution, means uniting one end of said elongated member to said metal liner element, and means uniting the other end of said elongated member to the walls of said vessel, said means for uniting said other end includinga. ring member united to the walls of said vessel upon which said elongated member extends to provide a substantial bearing surface for said elongated memher on said ring member, said other end of said elongated member being united to said ring member whereby as said elongated member and said ring member expand anystresses set up will force said elongated member against said ring member and will tend to cause said elongated member to flex in a region proximate said bearing surface.

4. A vessel, an insulation lining positioned adjacent the inner face of the walls of said vessel, said lining including a depth of insulation, a metal liner element between said insulation and the central space of said vessel, and impervious means united to said metal li'ner element and to the walls of said vessel supporting said metal liner element while permitting substantially unrestrained radial and longitudinal expansion thereof, and impervious means including an elongated cylindrical member normally disposed substantially parallel to said metal liner element, means uniting one end of said cylindrical member to said metal liner element, and means uniting the other end of said cylindrical member to the walls of said vessel, said means for uniting said other end including a ring member united to the walls of said vessel, said cylindrical member extending n the inner face of said ring member, said cylindrical member being united to said ring member along the end of said extending portion, whereby as said cylindrical member and said ring member expand stresses set up in said cylindrical member tend to force said cylindrical member against said ring member and tend to cause said cylindrical member to flex in a region adjacent said ring member.

5. A vessel, a depth of insulation disposed between the walls of said vessel and the central space thereof, a metal liner element formed of a plurality of separate sections separating said insulation from said central space, means support- 10 of said metal liner elements covered by said wear protectionmeans.

6. A vessel, a depth of insulation disposed between the walls of saidvessel and the central space thereof, a metal liner element formed of a plurality of separate sections separating said insulation from said central space, separate means encircling said sections and united thereto, said separate means supporting each of said sections independently while permitting substantially unrestrained expansion and contraction thereof, and wear members covering the joints uniting said sections to their respective supporting means, said wear members arranged in shingle fashion to provide continuous protection over the whole area of said metal liner elements covered by said wear members, each of said wear members being .shaped to conform to the shape of the portion of said liner element covered thereby.

7. A vessel, a'depth of insulation disposed between the walls of said vessel and the central space thereof, a metal liner element formed of a plurality of separate sections separating said insulation from said central space, means support ing said sections while permitting substantially unrestrained expansion and contraction thereof, adjacent ends of said sections being spaced to provide access into the space occupied by said insulation for pressure equalization, and wear members arranged in shingle fashion covering adjacent ones of said sections and shaped to conform tov the shape of said sections covered, each of said sections covered having united to the downstream end thereof one of said wear members positioned to cover said access space thereat, said ones of said wear members serving to guide said adjacent ends of said sections in their expansion and contraction movements.

8. A vessel, a depth of insulation disposed between the walls of said vessel and the central space thereof, a metal liner element formed of a plurality of separate sections between said insulation and the central space of said Vessel, means united to said sections supporting each of said sections while permitting substantially unrestrained expansion and contraction thereof, adjacent ends of said sections being spaced to provide access into the space occupied by said insula- "tion for pressure equalization, and wear members arranged in shingle fashion covering adjacent ones of said sections and shaped to conform to the shape of said sections covered, each of said sections covered having united to the downstream end thereof one of said wear members positioned to cover said access space and to guide said adjacent ends in their expansion and contraction movements, each of said sections covered having united thereto at the region of its joint with said supporting means another one of said wear members positioned to cover its said joint.

9. A vessel having a metal wall adapted to confine a flowing stream of material, a metal member positioned on said wall and projecting into said stream, a deposit of weld metal at the upstream end of said metal member uniting said metal member to said wall, and a metal wear member positioned on said wall against the upstream side of said weld metal and united to said wall, said metal wear member projecting into said stream to shield said weld metal from direct impingement by the material of said stream.

10. A vessel having a metal wall adapted to confine a flowing stream of material, a metal member positioned on said wall and projecting into said stream, a metal wear member positioned 11 on said wall and spaced from the upstream end of said metal member, and a deposit of weld metal in the space between said metal members and said metal wear member uniting them to each other and to said wall, said metal wear member protecting said deposit of weld metal from direct impingement by the material of said stream.

11. A vessel, a depth of insulation disposed between the walls of said vessel and the central space thereof, a metal liner element formed by a plurality of separate sections separating said insulation from said central space, adjacent ends of said sections being spaced to provide access into the space occupied by said insulation for pressure equalization, lap rings positioned to cover said access spaces and serving to guide said adjacent ends of said sections in their expansion and contraction movements, a plurality of wear rings, each of said lap rings having one of said wear rings positioned adjacent the upstream end thereof, and a deposit of weld metal between the lap ring andwear ring of each set of lap rings and wear rings uniting its respective lap ring and wear ring to each other and to the metal liner element, said wear rings each protecting their respective deposit of weld metal from direct impingement by the material handled.

12. An insulation lining, adapted to be positioned adjacent to the inner face of the walls of a vessel, comprising a depth of insulation, a metal liner element positioned against said insulation and adapted to confine the material handled to the central space of said vessel, and support means including an elongated cylindrical member and a T-shaped ring member, said T-shaped ring member surrounding said metal liner element, said cylindrical member surrounding said T-shaped ring member, said T-shaped ring member being united to said metal liner element on a narrow peripheral band disposed in a plane transverse to the longitudinal axis of said liner element and located adjacent to the middle of said metal liner element whereby longitudinal expansion and contraction of said metal liner element is unrestrained by said T-shaped ring member, said T shaped ring member having its central web united to said cylindrical member, and a second ring member united to said cylindrical member and to said vessel walls to provide a bearing surface for said cylindrical member whereby upon expansion said ring members tend to cause said cylindrical member to flex.

ELLIOTT R. THOMPSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 594,449 Weber Nov. 30, 1897 663,570 Haviland et al 'Dec. 11, 1900 2,254,964 Kettlewell Sept. 2, 1941 2,419,278 Motsenbocker Apr. 22, 1947 2,451,146 Baker et al Oct. 12, 1948 

